Chip scale package structure and method of forming the same

ABSTRACT

A semiconductor package structure including a semiconductor die having a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface. A first protective insulating layer covers the first and third surfaces of the semiconductor die. A redistribution layer (RDL) structure is electrically coupled to the semiconductor die and surrounded by the first protective insulating layer on the first surface of the semiconductor die. A first passivation layer covers the first protective insulating layer and the RDL structure. At least one conductive structure passes through the first passivation layer and is electrically coupled to the RDL structure. A method of forming the semiconductor package is also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Division of U.S. application Ser. No. 16/430,076, filed Jun. 3, 2019, which claims the benefit of U.S. Provisional Application No. 62/731,128 filed on Sep. 14, 2018. The entireties of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to semiconductor package technology, and in particular to a wafer level chip scale package (WLCSP) structure.

Description of the Related Art

Integrated circuit (IC) devices are fabricated in a semiconductor wafer and divided into individual chips. Afterwards, those chips are assembled in package form to be used in electronic products. The package provides a structure to support the chip and protect the chip from the environment. The package also provides electrical connections to and from the chip.

In recent years, as electronic products have been become increasingly multifunctional and have been scaled down in size, there is a desire for manufacturers of semiconductor devices to make more devices formed on a single semiconductor wafer, so that the electronic products that include these devices can be made more compact. This results in many new challenges to the structural and electrical design of the package.

Accordingly, a chip scale package (CSP) technology has been developed to satisfy the industry's demands (e.g., the smaller chip size and form factor). Moreover, a wafer level package (WLP) technology also has been introduced for cost-effective fabrication of packages. Such a technology is referred to as wafer-level chip scale package (WLCSP).

However, in the use of the WLCSP process, the surface of each chip in the respective package is exposed to the environment after the packages are separated from the package wafer. As a result, damage to the chip may occur, thereby reducing the reliability of the semiconductor packages. Thus, a novel semiconductor package structure and the fabrication method thereof are desirable.

BRIEF SUMMARY OF THE INVENTION

Semiconductor package structures and methods for forming the same are provided. An exemplary embodiment of a semiconductor package structure includes a semiconductor die having a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface. A first protective insulating layer covers the first surface and the third surface of the semiconductor die. A redistribution layer (RDL) structure is electrically coupled to the semiconductor die and surrounded by the first protective insulating layer on the first surface of the semiconductor die. A first passivation layer covers the first protective insulating layer and the RDL structure. At least one conductive structure passes through the first passivation layer and is electrically coupled to the RDL structure.

Another exemplary embodiment of a semiconductor package structure includes a semiconductor die having a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface. A first protective insulating layer covers the first surface of the semiconductor die. An RDL structure is electrically coupled to the semiconductor die and surrounded by the first protective insulating layer. A second protective insulating layer covers the second surface and the third surface of the semiconductor die. A first passivation layer covers the first protective insulating layer and the RDL structure. At least one conductive structure passes through the first passivation layer and is electrically coupled to the RDL structure.

An exemplary embodiment of a method of forming a semiconductor package structure including providing a semiconductor die. The semiconductor die has a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface. An RDL structure is formed on the first surface of the semiconductor die. The RDL structure is electrically coupled to the semiconductor die. A first protective insulating layer is formed to cover the first surface and the third surface of the semiconductor die and to surround the RDL structure. The first protective insulating layer and the RDL structure are covered with a first passivation layer. At least one conductive structure passing through the first passivation layer is formed to be electrically coupled to the RDL structure.

Another exemplary embodiment of a method of forming a semiconductor package structure including providing a semiconductor die. The semiconductor die has a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface. An RDL structure is formed on the first surface of the semiconductor die. The RDL structure is electrically coupled to the semiconductor die. A first protective insulating layer is formed to cover the first surface of the semiconductor die and to surround the RDL structure. A second protective insulating layer is formed to cover the second surface and the third surface of the semiconductor die. A first passivation layer is formed to cover the first protective insulating layer and the RDL structure. At least one conductive structure passing through the first passivation layer is formed to be electrically coupled to the RDL structure.

A detailed description is given in the following embodiments with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIGS. 1A to 1F are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments.

FIG. 2A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIG. 2B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIG. 3A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIG. 3B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIGS. 4A to 4E are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments.

FIG. 5A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIG. 5B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIGS. 6A to 6E are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments.

FIG. 7A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

FIG. 7B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments.

DETAILED DESCRIPTION OF THE INVENTION

The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is determined by reference to the appended claims.

The present invention will be described with respect to particular embodiments and with reference to certain drawings, but the invention is not limited thereto and is only limited by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated for illustrative purposes and not drawn to scale. The dimensions and the relative dimensions do not correspond to actual dimensions in the practice of the invention.

FIGS. 1A to 1F are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments of the disclosure. As shown in FIG. 1A, a substrate 100 is provided. In some embodiments, the substrate 100 may include a plurality of chip regions and a scribe line region that surrounds the plurality of chip regions and separates the adjacent chip regions from each other. To simplify the diagram, only two complete and adjacent chip regions C and a scribe line region S separating these chip regions C are depicted herein. The substrate 100 may be a silicon wafer so as to facilitate the wafer-level packaging process. For example, the substrate 100 may be a silicon substrate or another semiconductor substrate.

In some embodiments, the chip regions C of the substrate 100 include integrated circuits (not shown) therein. In some embodiments, an insulating layer 104 is formed on the substrate 100. The insulating layer 104 may serve as an inter-dielectric (ILD) layer, an inter-metal dielectric (IMD) layer, a passivation layer or a combination thereof. To simplify the diagram, only a flat layer is depicted herein. In some embodiments, the insulating layer 104 is made of an inorganic material, such as silicon oxide (SiO_(x)), silicon nitride (SiN_(x)), silicon oxynitride (SiON), or a combination thereof, or another suitable insulating material.

Moreover, the insulating layer 104 includes one or more conductive pads 102 therein. The conductive pads 102 correspond to the chip regions C of the substrate 100 and are adjacent to the upper surface of the substrate 100. The conductive pad 122 may be formed of metal, such as copper, aluminum, or another suitable metal material. To simplify the diagram, only one conductive pad 102 formed on the substrate 100 in each chip region C and exposed from the insulating layer 104 is depicted herein as an example. In some embodiments, the ICs in the chip region C is electrically connected to the corresponding conductive pad 102. The aforementioned structure define a number of semiconductor dies/chips after the chip regions C are separated from each other by dicing the scribe line region S of the substrate 100.

In some embodiments, a conductive layer (not shown), such as a metal layer, is formed on the insulating layer 104 and passing through the insulating layer 104 to electrically couple to the exposed pads 102 in the chip regions C. Afterwards, the conductive layer is patterned to form a redistribution layer (RDL) structure 106 in each of the chip regions C, so that the RDL structure 106 is electrically coupled to the subsequent formed semiconductor die, as shown in FIG. 1A.

As shown in FIG. 1B, in some embodiments, the chip regions C are separated from each other by dicing the scribe line region S of the substrate 100 to form semiconductor dies with the RDL structures 106 thereon. The formed semiconductor die may be a system on chip (SOC) integrated circuit die. The SOC integrated circuit die, for example, may include a logic die including a central processing unit (CPU), a graphics processing unit (GPU), a dynamic random access memory (DRAM) controller or any combination thereof. Each of semiconductor dies includes a substrate 100, at least one conductive pad 102 formed on the substrate 100, and an insulating layer 104 formed over the substrate 100 and having an opening to expose the conductive pad 102. Moreover, the semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b.

As shown in FIG. 1B, in some embodiments, a carrier substrate 200 with an adhesive layer 202 formed thereon is provided. The carrier substrate 200 may be made of silicon, glass, ceramic or the like, and may have a shape that is the same or similar to the semiconductor wafer, and therefore the carrier substrate 200 is sometimes referred to as a carrier wafer. The adhesive layer 202 may be made of a light-to-heat conversion (LTHC) material or another suitable material. Afterwards, in some embodiments, the second surface 101 b of each semiconductor die that has an RDL structure 106 formed on the first surface 101 a of the semiconductor die is mounted onto the carrier substrate 200 via the adhesive layer 202 using a pick-and-place process.

Next, in some embodiments, a protective insulating layer 110 is formed to cover the first surface 101 a and the third surface 101 c of the semiconductor dies and to surround the RDL structures 106, so that each of the formed semiconductor dies with an RDL structure 106 thereon is encapsulated by the protective insulating layer 110. In some embodiments, the protective insulating layer 110 protects the semiconductor dies from the environment, thereby preventing the semiconductor die in the subsequently formed semiconductor package structure from damage due to, for example, the stress, the chemicals and/or the moisture.

In some embodiments, the protective insulating layer 110 is made of an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material. In some embodiments, the protective insulating layer 110 is made of an epoxy molding compound (EMC) and formed by a molding process. For example, the protective insulating layer 110 (such as in an epoxy or resin) may be applied while substantially liquid, and then may be cured through a chemical reaction. The protective insulating layer 110 may be an ultraviolet (UV) or thermally cured polymer applied as a gel or malleable solid capable of being formed around the semiconductor dies, and then may be cured through a UV or thermal curing process. The protective insulating layer 110 may be cured with a mold (not shown).

After the protective insulating layer 110 is formed, the semiconductor dies with RDL structures 106 encapsulated by the protective insulating layer 110 are de-bonded from the carrier substrate 200, as shown in FIG. 1C. In some embodiments, a de-bonding process is performed by exposing the adhesive layer 202 (shown in FIG. 1B) using a laser or UV light when the adhesive layer 202 is made of an LTHC material. The LTHC material may be decomposed due to generated heat from the laser or UV light, and hence the carrier substrate 200 is removed from the structure including the semiconductor dies, the RDL structures 106, and the protective insulating layer 110. As a result, the second surface 101 b of each semiconductor die is exposed from the protective insulating layer 110. The resulting structure is shown in FIG. 1C.

In some embodiments, after the carrier substrate 200 is removed by the de-bonding process, a grinding process is performed on the top surface of the protective insulating layer 110 until the RDL structures 106 are exposed from the protective insulating layer 110, as shown in FIG. 1D. For example, the top surface of the protective insulating layer 110 may be grinded by a chemical mechanical polishing (CMP) process or another suitable grinding process.

Afterwards, the protective insulating layer 110 and the RDL structures 106 are covered with a passivation layer 112, as shown in FIG. 1E. In some embodiments, the passivation layer 112 is formed on the protective insulating layer 110 and the RDL structures 106 by a coating process or another suitable deposition process. Afterwards, the passivation layer 112 is patterned by lithography or a combination of lithograph and etching to form openings that expose the RDL structures 106. In some embodiments, the passivation layer 112 is made of a material that is different from the material of the protective insulating layer 110. In some embodiments, the passivation layer 112 is made of polyimide or polybenzoxazole (PBO).

In some embodiments, during patterning the passivation layer 112, the passivation layer 112 is also divided into several portions, so that each of the semiconductor dies is covered by a respective portion of passivation layer 112. In some other embodiments, the passivation layer 112 is divided into several portions by the subsequent dicing process.

After openings are formed in the passivation layer 112, conductive structures 120 respectively pass through the passivation layer 112 via those openings formed in the passivation layer 112, as shown in FIG. 1E. In some embodiments, the conductive structures 120 fill into the openings formed in the passivation layer 112, so that each of the conductive structures 120 is electrically coupled to the respective exposed RDL structure 106 under the opening in the passivation layer 112.

In some embodiments, the conductive structure 120 includes an optional under-bump metallurgy (UBM) layer 122 and a solder bump 124 on the UBM layer 122. In some other embodiments, the conductive structure 120 includes a conductive bump structure such as a copper bump, a conductive pillar structure, a conductive wire structure, or a conductive paste structure.

After the conductive structures 120 are formed, an optional protective insulating layer 130 is formed to cover the exposed second surfaces 101 b of the semiconductor dies, as shown in FIG. 1F. The protective insulating layer 130 is sometimes referred to as a die backside film (DBF) that is made of a thermoset material, such as an epoxy resin material. In some other embodiments, the protective insulating layer 130 is made of a material that is the same as the material of the protective insulating layer 110. For example, the protective insulating layer 130 is made of an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material.

In some embodiments, after the protective insulating layer 130 is formed, a singulation is carried out to saw through the formed structure shown in FIG. 1F. For example, a dicing process may be performed on the formed structure shown in FIG. 1F. As a result, multiple separate semiconductor package structures are formed.

FIG. 2A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. In FIG. 2A, one of the semiconductor package structures 10 a that is formed by dicing the formed structure shown in FIG. 1F is shown. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIGS. 1A to 1F may be omitted for brevity. In some embodiments, the semiconductor package structure 10 a includes a semiconductor die that includes a substrate 100, at least one conductive pad 102 formed on the substrate 100, and an insulating layer 104 formed over the substrate 100 and having an opening to expose the conductive pad 102, as shown in FIG. 2A. The semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b.

In some embodiments, the semiconductor package structure 10 a further includes a protective insulating layer 110 that covers the first surface 101 a and the third surface 101 c of the semiconductor die, and a protective insulating layer 130 that covers the second surface 101 b of the semiconductor die. The thickness of the portion of the protective insulating layer 110 covering the first surface 101 a and the thickness of the of the portion of the protective insulating layer 110 covering the third surface 101 c of the semiconductor die can be adjusted, so as to fine-tune the protection ability of the semiconductor package structure 10 a.

In some embodiments, the protective insulating layer 110 and the protective insulating layer 130 are made of the same material or different materials. For example, such a material may include an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material. Alternatively, the protective insulating layer 110 is made of an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material, and the protective insulating layer 130 is made of a DBF material that includes a thermoset material, such as an epoxy resin material.

In some embodiments, the semiconductor package structure 10 a further includes an RDL structure 106 electrically coupled to the semiconductor die via the conductive pad 102 and surrounded by the protective insulating layer 110 on the first surface 101 a of the semiconductor die.

In some embodiments, the semiconductor package structure 10 a further includes a passivation layer 112 covering the RDL structure 106 and a portion of the protective insulating layer 110 surrounding the RDL structure 106. The passivation layer 112 may be made of polyimide or polybenzoxazole (PBO).

In some embodiments, the semiconductor package structure 10 a further includes at least one conductive structure 120 that includes an optional UBM layer 122 and a solder bump 124 and passes through the passivation layer 110, so as to be electrically coupled to the semiconductor die through the RDL structure 106.

In some embodiments, the semiconductor package structure 10 a shown in FIG. 2A is a CSP structure. The CSP structure may include an SOC package. Moreover, the semiconductor package structure 10 a may be mounted on a base (not shown). The base may include a printed circuit board (PCB) and may be formed of polypropylene (PP). Alternatively, the base may include a package substrate. The semiconductor package structure 10 a may be mounted on the base by a bonding process. For example, the semiconductor package structure 10 a may be mounted on the base by the bonding process and electrically coupled to the base using the conductive structures 120 as connectors.

FIG. 2B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 2A may be omitted for brevity. In some embodiments, the semiconductor package structure 10 b is similar to the semiconductor package structure 10 a shown in FIG. 2A. Compared to the semiconductor package structure 10 a, there is no protective insulating layer 130 formed in the package structure 10 b, and hence the second surface 101 b of the semiconductor die is exposed to the environment. In some embodiments, the semiconductor package structure 10 b is formed by a method that is similar to the method shown in FIGS. 1A to 1F, except that the formation of the protective insulating layer 130, as shown in FIG. 1F, is omitted. Namely, after the structure shown in FIG. 1E is formed, a singulation is carried out to saw through the formed structure shown in FIG. 1E.

FIG. 3A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 2A may be omitted for brevity. In some embodiments, the semiconductor package structure 10 c is similar to the semiconductor package structure 10 a shown in FIG. 2A. Compared to the semiconductor package structure 10 a, the semiconductor package structure 10 c further includes a passivation layer 105 formed between the first surface 101 a of the semiconductor die and the RDL structure 106 and covered by the protective insulating layer 110. In some embodiments, the material and the method used for the passivation layer 105 are the same as or similar to those used for the passivation layer 112. For example, the passivation layer 105 is made of polyimide or polybenzoxazole (PBO). In some embodiments, the semiconductor package structure 10 c is formed by a method that is similar to the method shown in FIGS. 1A to 1F, except that an additional passivation layer 105 is formed prior to the formation of the RDL structure 106. Prior to the formation of the RDL structure 106, at least one opening is formed in the passivation layer 105, so that the passivation layer 105 exposes the conductive pad 102 and surrounds the opening formed in the insulating layer 104.

FIG. 3B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIGS. 2A and 3A may be omitted for brevity. In some embodiments, the semiconductor package structure 10 d is similar to the semiconductor package structure 10 c shown in FIG. 3A. Compared to the semiconductor package structure 10 c, there is no protective insulating layer 130 formed in the package structure 10 d, and hence the second surface 101 b of the semiconductor die is exposed to the environment. In some embodiments, the semiconductor package structure 10 d is formed by a method that is similar to the method used for forming the semiconductor package structure 10 c, except that the formation of the protective insulating layer 130 is omitted.

FIGS. 4A to 4E are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments of the disclosure. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIGS. 1A to 1F may be omitted for brevity. As shown in FIG. 4A, a structure as shown in FIG. 1A is provided. Afterwards, a protective insulating layer 110 a to cover the first surface 101 a of each semiconductor die and surround each RDL structure 106, so that the top surfaces and sidewalls of the RDL structures 106 are covered or encapsulated by the protective insulating layer 110 a. In some embodiments, the protective insulating layer 110 a is made of an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material. In some embodiments, the protective insulating layer 110 a is formed by a coating process, a molding process, or another suitable process.

As shown in FIG. 4B, in some embodiments, after the protective insulating layer 110 a is formed, the chip regions C are separated from each other by dicing the scribe line region S of the substrate 100 to form semiconductor dies with the RDL structures 106 thereon. The formed semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b. Moreover, the protective insulating layer 110 a has a sidewall 109 that is substantially aligned with the third surface 101 c of the semiconductor die.

Still referring to FIG. 4B, in some embodiments, a carrier substrate 200 with an adhesive layer 202 formed thereon is provided. Afterwards, in some embodiments, each of the formed semiconductor dies with an RDL structure 106 formed on the first surface 101 a of the semiconductor die is mounted onto the carrier substrate 200 by attaching the top surface of the protective insulating layer 110 a to the adhesive layer 202 using a pick-and-place process. As a result, the second surface 101 b of each semiconductor die is opposite the carrier substrate 200.

Next, in some embodiments, a protective insulating layer 110 is formed using a molding process to cover the second surface 101 b and the third surface 101 c of the semiconductor dies and surround the protective insulating layer 110 a, so that the protective insulating layer 110 extends from the third surface 101 c of each semiconductor die to the sidewall 109 of the respective protective insulating layer. As a result, each of the formed semiconductor dies with an RDL structure 106 thereon is encapsulated by a protective structure including the protective insulating layer 110 a and the protective insulating layer 110.

In some embodiments, the protective structure protects the semiconductor dies from the environment, thereby preventing the semiconductor die in the subsequently formed semiconductor package structure from damage due to, for example, the stress, the chemicals and/or the moisture. In some embodiments, the protective insulating layer 110 of the protective structure is formed by a molding process while the protective insulating layer 110 a of the protective structure is formed by a coating process.

After the protective structure is formed, the semiconductor dies with RDL structures 106 encapsulated by the protective structure are de-bonded from the carrier substrate 200 by a de-bonding process as shown in FIG. 1C. The resulting structure is shown in FIG. 4C.

In some embodiments, after the carrier substrate 200 is removed by the de-bonding process, a grinding process is performed on the protective insulating layer 110 a above the RDL structures 106 and a portion of the protective insulating layer 110 surrounding the protective insulating layer 110 a until the RDL structures 106 are exposed from the protective insulating layer 110 a, as shown in FIG. 4D. For example, the protective insulating layer 110 a and the protective insulating layer 110 may be grinded by a CMP process or another suitable grinding process.

Afterwards, the protective insulating layer 110 a and the RDL structures 106 are covered with a patterned passivation layer 112, as shown in FIG. 4E. In some embodiments, the passivation layer 112 is made of a material that is different from the material of the protective insulating layer 110 a and the material of the protective insulating layer 110. In some embodiments, during patterning the passivation layer 112, the passivation layer 112 is also divided into several portions, so that each of the semiconductor dies is covered by a respective portion of passivation layer 112. In some other embodiments, the passivation layer 112 is divided into several portions by the subsequent dicing process.

After openings are formed in the passivation layer 112, conductive structures 120 including an optional UBM layer 122 and a solder bump 124 respectively pass through the passivation layer 112 via those openings, as shown in FIG. 4E. As a result, each of the conductive structures 120 is electrically coupled to the respective exposed RDL structure 106.

In some embodiments, after the conductive structures 120 is formed, a singulation (e.g., a dicing process) is carried out to saw through the formed structure shown in FIG. 4E. As a result, multiple separate semiconductor package structures are formed.

FIG. 5A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. In FIG. 5A, one of the semiconductor package structures 20 a that is formed by dicing the formed structure shown in FIG. 4E is shown. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIGS. 4A to 4E may be omitted for brevity. In some embodiments, the semiconductor package structure 20 a includes a semiconductor die that includes a substrate 100, at least one conductive pad 102 formed on the substrate 100, and an insulating layer 104 formed over the substrate 100 and having an opening to expose the conductive pad 102, as shown in FIG. 5A. The semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b.

In some embodiments, the semiconductor package structure 20 a further includes a protective insulating layer 110 a that covers the first surface 101 a of the semiconductor die, and a protective insulating layer 110 that covers the second surface 101 b and the third surface 101 c of the semiconductor die and that surrounds the protective insulating layer 110 a. The protective insulating layer 110 a has a sidewall 109 that is substantially aligned with the third surface 101 c of the semiconductor die. The protective insulating layer 110 extends from the third surface 101 c of the semiconductor die to the sidewall 109 of the protective insulating layer 110 a. The thickness of the protective insulating layer 110 a covering the first surface 101 a and the thickness of the protective insulating layer 110 covering the second surface 101 b and the third surface 101 c of the semiconductor die can be adjusted, so as to fine-tune the protection ability of the semiconductor package structure 20 a.

In some embodiments, the protective insulating layer 110 a and the protective insulating layer 110 are made of the same material or different materials. For example, such a material may include an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material.

In some embodiments, the semiconductor package structure 20 a further includes an RDL structure 106 electrically coupled to the semiconductor die via the conductive pad 102 and surrounded by the protective insulating layer 110 a.

In some embodiments, the semiconductor package structure 20 a further includes a passivation layer 112 covering the RDL structure 106 and a portion of the protective insulating layer 110 a surrounding the RDL structure 106. Moreover, the passivation layer 112 is made of for example, polyimide or polybenzoxazole (PBO).

In some embodiments, the semiconductor package structure 20 a further includes at least one conductive structure 120 that includes an optional UBM layer 122 and a solder bump 124 and passes through the passivation layer 110, so as to be electrically coupled to the semiconductor die through the RDL structure 106.

In some embodiments, the semiconductor package structure 20 a shown in FIG. 5A is a CSP structure. The CSP structure may include an SOC package. Moreover, the semiconductor package structure 20 a may be mounted on a base (not shown). The base may include a printed circuit board (PCB) and may be formed of polypropylene (PP). Alternatively, the base may include a package substrate. Similar to the semiconductor package structure 10 a, the semiconductor package structure 20 a may be mounted on the base by a bonding process and electrically coupled to the base using the conductive structures 120 as connectors.

FIG. 5B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 5A may be omitted for brevity. In some embodiments, the semiconductor package structure 20 b is similar to the semiconductor package structure 20 a shown in FIG. 5A. Compared to the semiconductor package structure 20 a, the semiconductor package structure 20 b further includes a passivation layer 105 formed between the first surface 101 a of the semiconductor die and the RDL structure 106 and covered by the protective insulating layer 110 a. In some embodiments, the material and the method used for the passivation layer 105 are the same as or similar to those used for the passivation layer 112 and different from those used for the protective insulating layer 110 a and those used for the protective insulating layer 110. In some embodiments, the semiconductor package structure 20 b is formed by a method that is similar to the method shown in FIGS. 4A to 4E, except that an additional passivation layer 105 is formed prior to the formation of the RDL structure 106. Prior to the formation of the RDL structure 106, at least one opening is formed in the passivation layer 105, so that the passivation layer 105 exposes the conductive pad 102 and surrounds the opening formed in the insulating layer 104.

FIGS. 6A to 6E are cross-sectional views of an exemplary method of forming a semiconductor package structure in accordance with some embodiments of the disclosure. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 1A to 1F or 4A to 4E may be omitted for brevity. As shown in FIG. 6A, a structure as shown in FIG. 1A is provided. Afterwards, the chip regions C are separated from each other by dicing the scribe line region S of the substrate 100 to form semiconductor dies with the RDL structures 106 thereon. The formed semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b.

As shown in FIG. 6A, in some embodiments, a carrier substrate 200 with an adhesive layer 202 formed thereon is provided. Afterwards, in some embodiments, each of the formed semiconductor dies with an RDL structure 106 formed on the first surface 101 a of the semiconductor die is mounted onto the carrier substrate 200 by attaching the top surface and sidewall surface of the RDL structure 106 to the adhesive layer 202 using a pick-and-place process. As a result, the second surface 101 b of each semiconductor die is opposite the carrier substrate 200.

Next, in some embodiments, a protective insulating layer 110 is formed using a molding process to cover the second surface 101 b and the third surface 101 c of the semiconductor dies and surround the protective insulating layer 110 a, so that the protective insulating layer 110 extends from the third surface 101 c of each semiconductor die to the sidewall 109 of the respective protective insulating layer.

In some embodiments, after the protective insulating layer 110 is formed, the semiconductor dies with RDL structures 106 are de-bonded from the carrier substrate 200 by a de-bonding process (as shown in FIG. 1C). The resulting structure is shown in FIG. 6B.

In some embodiments, after the de-bonding process, a protective insulating layer 110 a is formed by a coating process to cover the first surface 101 a of each semiconductor die and surround each RDL structure 106, as shown in FIG. 6C. As a result, the top surfaces and sidewalls of the RDL structures 106 are covered or encapsulated by the protective insulating layer 110 a. Moreover, a portion of the protective insulating layer 110 covering the third surface 101 c of the semiconductor die is capped by the protective insulating layer 110 a. In some other embodiments, the protective insulating layer 110 a is formed by a molding process or another suitable process.

Due to the formation of a protective structure including the protective insulating layer 110 a and the protective insulating layer 110, each of the formed semiconductor dies with an RDL structure 106 thereon is encapsulated. The protective structure protects the semiconductor dies from the environment, thereby preventing the semiconductor die in the subsequently formed semiconductor package structure from damage due to, for example, the stress, the chemicals and/or the moisture.

In some embodiments, after the protective structure is formed, a grinding process is performed on the protective insulating layer 110 a above the RDL structures 106 until the RDL structures 106 are exposed from the protective insulating layer 110 a, as shown in FIG. 6D. For example, the protective insulating layer 110 a may be grinded by a CMP process or another suitable grinding process.

Afterwards, the protective insulating layer 110 a and the RDL structures 106 are covered with a patterned passivation layer 112, as shown in FIG. 6E. In some embodiments, the passivation layer 112 is made of a material that is different from the material of the protective insulating layer 110 a and the material of the protective insulating layer 110. In some embodiments, during patterning the passivation layer 112, the passivation layer 112 is also divided into several portions, so that each of the semiconductor dies is covered by a respective portion of passivation layer 112. In some other embodiments, the passivation layer 112 is divided into several portions by the subsequent dicing process.

After openings are formed in the passivation layer 112, conductive structures 120 including an optional UBM layer 122 and a solder bump 124 respectively pass through the passivation layer 112 via those openings, as shown in FIG. 6E. As a result, each of the conductive structures 120 is electrically coupled to the respective exposed RDL structure 106.

In some embodiments, after the conductive structures 120 is formed, a singulation (e.g., a dicing process) is carried out to saw through the formed structure shown in FIG. 6E. As a result, multiple separate semiconductor package structures are formed. In some embodiments, in the semiconductor package structure, the protective insulating layer 110 a has a sidewall and a portion of the protective insulating layer covering the third surface 101 c of the semiconductor die has a sidewall, and those sidewalls are substantially aligned with each other.

FIG. 7A is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. In FIG. 7A, one of the semiconductor package structures 30 a that is formed by dicing the formed structure shown in FIG. 6E is shown. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 1A to 1F or 4A to 4E may be omitted for brevity. In some embodiments, the semiconductor package structure 30 a includes a semiconductor die that includes a substrate 100, at least one conductive pad 102 formed on the substrate 100, and an insulating layer 104 formed over the substrate 100 and having an opening to expose the conductive pad 102, as shown in FIG. 7A. The semiconductor die has a first surface 101 a (e.g., an active surface of the semiconductor die), a second surface 101 b (e.g., a non-active surface of the semiconductor die) opposite the first surface 101 a, and a third surface 101 c (e.g., a sidewall surface of the semiconductor die) adjoined between the first surface 101 a and the second surface 101 b.

In some embodiments, the semiconductor package structure 30 a further includes a protective insulating layer 110 a that covers the first surface 101 a of the semiconductor die, and a protective insulating layer 110 that covers the second surface 101 b and the third surface 101 c of the semiconductor die and that surrounds the protective insulating layer 110 a. The protective insulating layer 110 a has a sidewall 109 and a portion of the protective insulating layer 110 a covering the third surface 101 c of the semiconductor die has a sidewall 113. In some embodiments, the sidewall 109 is substantially aligned with the sidewall 113. Moreover, the portion of the protective insulating layer 110 covering the third surface 101 c of the semiconductor die is capped by the protective insulating layer 110 a. The thickness of the protective insulating layer 110 a covering the first surface 101 a and the thickness of the protective insulating layer 110 covering the second surface 101 b and the third surface 101 c of the semiconductor die can be adjusted, so as to fine-tune the protection ability of the semiconductor package structure 30 a.

In some embodiments, the protective insulating layer 110 a and the protective insulating layer 110 are made of the same material or different materials. For example, such a material may include an epoxy molding compound (EMC), an Ajinomoto™ Build-up Film (ABF), or an acrylic-based material.

In some embodiments, the semiconductor package structure 30 a further includes an RDL structure 106 electrically coupled to the semiconductor die via the conductive pad 102 and surrounded by the protective insulating layer 110 a.

In some embodiments, the semiconductor package structure 30 a further includes a passivation layer 112 covering the RDL structure 106 and a portion of the protective insulating layer 110 a surrounding the RDL structure 106. Moreover, the passivation layer 112 is made of for example, polyimide or polybenzoxazole (PBO).

In some embodiments, the semiconductor package structure 30 a further includes at least one conductive structure 120 that includes an optional UBM layer 122 and a solder bump 124 and passes through the passivation layer 110, so as to be electrically coupled to the semiconductor die through the RDL structure 106.

In some embodiments, the semiconductor package structure 30 a shown in FIG. 7A is a CSP structure. The CSP structure may include an SOC package. Moreover, the semiconductor package structure 30 a may be mounted on a base (not shown). The base may include a printed circuit board (PCB) and may be formed of polypropylene (PP). Alternatively, the base may include a package substrate. Similar to the semiconductor package structure 10 a or 20 a, the semiconductor package structure 30 a may be mounted on the base by a bonding process and electrically coupled to the base using the conductive structures 120 as connectors.

FIG. 7B is a cross-sectional view of an exemplary semiconductor package structure in accordance with some embodiments. Descriptions of elements of the embodiments hereinafter that are the same as or similar to those previously described with reference to FIG. 7A may be omitted for brevity. In some embodiments, the semiconductor package structure 30 b is similar to the semiconductor package structure 30 a shown in FIG. 7A. Compared to the semiconductor package structure 30 a, the semiconductor package structure 30 b further includes a passivation layer 105 formed between the first surface 101 a of the semiconductor die and the RDL structure 106 and covered by the protective insulating layer 110 a. In some embodiments, the material and the method used for the passivation layer 105 are the same as or similar to those used for the passivation layer 112 and from those used for the protective insulating layer 110 a and those used for the protective insulating layer 110. In some embodiments, the semiconductor package structure 30 b is formed by a method that is similar to the method shown in FIGS. 6A to 6E, except that an additional passivation layer 105 is formed prior to the formation of the RDL structure 106. Prior to the formation of the RDL structure 106, at least one opening is formed in the passivation layer 105, so that the passivation layer 105 exposes the conductive pad 102 and surrounds the opening formed in the insulating layer 104.

According to the foregoing embodiments, the semiconductor package structure is designed to fabricate a protective structure in the semiconductor package structure to cover or encapsulate the semiconductor die in the semiconductor package structure. The protective structure includes one or more protective insulating layers to protect the semiconductor die from the environment, thereby preventing the semiconductor die in the semiconductor package structure from damage due to, for example, the stress, the chemicals and/or the moisture.

Due to the topside protection of semiconductor die, the reliability of the semiconductor package structure can be maintained during the subsequent thermal process (such as a surface mount technology (SMT) process or a bonding process). Moreover, the RDL structure formed on the semiconductor die is also protected by the protective structure, so as to keep its electrical and thermal performance. In addition, due to the sidewall protection of semiconductor die, the semiconductor die in the semiconductor package structure can be prevented from chipping when the CSP structure is placed in a test socket for performing a test process.

While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. 

What is claimed is:
 1. A method of forming a semiconductor package structure, comprising: providing a semiconductor die, wherein the semiconductor die has a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface; forming a redistribution layer (RDL) structure on the second surface of the semiconductor die, wherein the RDL structure is electrically coupled to the semiconductor die; forming a first protective insulating layer to cover the first surface and the third surface of the semiconductor die; covering the RDL structure with a first passivation layer; forming at least one conductive structure passing through the first passivation layer to be electrically coupled to the RDL structure; forming an insulating layer on the second surface of the semiconductor die; forming a second passivation layer between the insulating layer and the first passivation layer; and forming a second protective insulating layer on the second surface of the semiconductor die, wherein the first protective insulating layer and the second protective insulating layer are formed of different materials, wherein the second protective insulating layer includes an acrylic-based material, wherein a top surface of the first protective insulating layer is coplanar with a top surface of the insulating layer.
 2. The method as claimed in claim 1, wherein the first protective insulating layer and the second protective insulating layer respectively comprise an epoxy molding compound (EMC).
 3. The method as claimed in claim 1, wherein the first protective insulating layer is formed by a molding process.
 4. The method as claimed in claim 1, wherein the second passivation layer is formed before forming the RDL structure.
 5. The method as claimed in claim 4, wherein the first passivation layer comprises a material that is the same as a material of the second passivation layer and different from a material of the first protective insulating layer.
 6. The method as claimed in claim 4, wherein the first passivation layer and the second passivation layer comprise polyimide or polybenzoxazole (PBO).
 7. The method as claimed in claim 1, wherein: the second passivation layer is formed before forming the RDL structure; and the second protective insulating layer is formed after forming the at least one conductive structure.
 8. The method as claimed in claim 1, wherein the at least one conductive structure comprises an under-bump metallurgy (UBM) layer and a solder bump on the UBM layer.
 9. A method of forming a semiconductor package structure, comprising: providing a semiconductor die, wherein the semiconductor die has a first surface, a second surface opposite the first surface, and a third surface adjoined between the first surface and the second surface; forming a redistribution layer (RDL) structure on the first surface of the semiconductor die, wherein the RDL structure is electrically coupled to the semiconductor die; forming a first protective insulating layer to cover the first surface of the semiconductor die and to surround the RDL structure; forming a second protective insulating layer to cover the second surface and the third surface of the semiconductor die; forming a first passivation layer to cover the first protective insulating layer and the RDL structure; and forming at least one conductive structure passing through the first passivation layer to be electrically coupled to the RDL structure, wherein the first protective insulating layer is formed by a coating process after forming the second protective insulating layer using a molding process.
 10. The method as claimed in claim 9, wherein the first protective insulating layer and the second protective insulating layer respectively comprise an epoxy molding compound (EMC) or an acrylic-based material.
 11. The method as claimed in claim 9, further comprising forming a second passivation layer on the first surface of the semiconductor die before forming the RDL structure.
 12. The method as claimed in claim 11, wherein the first passivation layer comprises a material that is the same as a material of the second passivation layer and different from a material of the first protective insulating layer and a material of the second protective insulating layer.
 13. The method as claimed in claim 9, wherein the first protective insulating layer has a sidewall that is substantially aligned with the third surface of the semiconductor die, and wherein the second protective insulating layer extends from the third surface of the semiconductor die to the sidewall of the first protective insulating layer.
 14. The method as claimed in claim 9, wherein the first protective insulating layer has a first sidewall and a portion of the second protective insulating layer covering the third surface of the semiconductor die has a second sidewall, and wherein the first sidewall is substantially aligned with the second sidewall.
 15. The method as claimed in claim 9, wherein a portion of the second protective insulating layer covering the third surface of the semiconductor die is capped by the first protective insulating layer.
 16. The method as claimed in claim 9, wherein the at least one conductive structure comprises an under-bump metallurgy (UBM) layer and a solder bump on the UBM layer. 